Pump-and-probe experiments, involving times ranging from tens of ps to ms, revealed a transient optical absorption of the F-center plus CN- defect complex, FH(CN-). Its structure was explained in terms of electronic-vibrational transitions of the defect, in which the CN- stretching mode was highly excited. A detailed analysis revealed an appreciable change in the vibronic energies in the excited electronic state, due to nonlinear coupling. The time which was required for electron-vibrational energy transfer was equal to about 70ns in the case of CsBr. It was shorter in the case of CsCl. These results demonstrated that the transfer took place in the relaxed excited state. It was also found that a 10ms recovery component was due to vibrational relaxation.

D.Samiec, H.Stolz, W.Von der Osten: Physical Review B, 1996, 53[14], R8811-4